Geographic Variation in Diagnosis Frequency and Risk of Death Among Medicare Beneficiaries, by H. Gilbert Welch, Sandra M. Sharp, Dan J. Gottlieb, Jonathan S. Skinner, John E. Wennberg (JAMA)
Context. Because diagnosis is typically thought of as purely a patient attribute, it is considered a critical factor in risk-adjustment policies designed to reward efficient and high-quality care.
Objective. To determine the association between frequency of diagnoses for chronic conditions in geographic areas and case-fatality rate among Medicare beneficiaries.
Design, Setting, and Participants. Cross-sectional analysis of the mean number of 9 serious chronic conditions (cancer, chronic obstructive pulmonary disease, coronary artery disease, congestive heart failure, peripheral artery disease, severe liver disease, diabetes with end-organ disease, chronic renal failure, and dementia) diagnosed in 306 hospital referral regions (HRRs) in the United States; HRRs were divided into quintiles of diagnosis frequency. Participants were 5 153 877 fee-for-service Medicare beneficiaries in 2007.
Main Outcome Measures. Age/sex/race–adjusted case-fatality rates.
Results. Diagnosis frequency ranged across HRRs from 0.58 chronic conditions in Grand Junction, Colorado, to 1.23 in Miami, Florida (mean, 0.90 [95% confidence interval {CI}, 0.89-0.91]; median, 0.87 [interquartile range, 0.80-0.96]). The number of conditions diagnosed was related to risk of death: among patients diagnosed with 0, 1, 2, and 3 conditions the case-fatality rate was 16, 45, 93, and 154 per 1000, respectively. As regional diagnosis frequency increased, however, the case fatality associated with a chronic condition became progressively less. Among patients diagnosed with 1 condition, the case-fatality rate decreased in a stepwise fashion across quintiles of diagnosis frequency, from 51 per 1000 in the lowest quintile to 38 per 1000 in the highest quintile (relative rate, 0.74 [95% CI, 0.72-0.76]). For patients diagnosed with 3 conditions, the corresponding case-fatality rates were 168 and 137 per 1000 (relative rate, 0.81 [95% CI, 0.79-0.84]).
Conclusion. Among fee-for-service Medicare beneficiaries, there is an inverse relationship between the regional frequency of diagnoses and the case-fatality rate for chronic conditions.
有关end-of-life care的名词：
In simplistic terms, palliative care focuses on improving quality of life and helping patients clarify their goals, regardless of prognosis. 与Medication(Drug Delivery)不同,Palliative care is a process that depends upon human interaction, especially since clarifying goals of care is important.所以Palliative Care的影响因素比较多，不可能有药物治疗那样直接的效果，所以即使随机控制试验(RCT)也未必能那么有效（如病人特殊性、咨询治疗时间长度的变异）。
Hospice is a subset of palliative care that focuses on persons who are believed to have a life expectancy of 6 months or less, and provides interdisciplinary care designed to address symptoms, maximize quality of life, and address the wholistic needs of both patient and family.
另：
2010年8月NEJM上一篇文章使用randomized control trial (RCT)的方法showed that patients receiving early palliative care had better quality of life, lower resource use (costs), and longer life expectancy (~12 months for treatment v. ~9 months for controls of patients with stage IV lung cancer)。毫无疑问，这样的研究内部效度肯定非常好。为了推进其外部效度的检验，一想NIH赞助的Palliative Care Research Cooperative 研究将开展多点临床试验。
what is PCPs?
primary care programs, such as family medicine (also called family practice or general practice in some countries), pediatrics or internal medicine. Some HMOs consider gynecologists as PCPs for the care of women, and have allowed certain subspecialists to assume PCP responsibilities for selected patient types, such as allergists caring for people with asthma and nephrologists acting as PCPs for patients on kidney dialysis.
